There have recently been growing consumers' demands for materials for use in so-called manicure, pedicure, and sculpture, which decorate or reinforce nails by applying resin compositions and the like to the nails, for the purpose of decorating the nails, or for the purpose of decorating artificial nails bonded onto nails, or for the purpose of preventing nails from being chipped or peeled due to external forces applied during exercises and the like. Here, the mainstream coating material used for decoration or reinforcement includes those obtained by dissolving nitrocellulose-based lacquers in organic solvents and adding pigments of various color tones to the solutions.
Besides these, various coating materials have been used, including those obtained by adding pigments and plasticizers in systems of alkyd resins and the like. These coating materials provide coatings excellent in gloss in a short period of time when the coating materials are applied to keratins of nails or the like and then organic solvents are evaporated. The coating formed on the nail can be readily wiped off by using an organic solvent such as acetone.
These types of coating materials, however, have poor adhesiveness with natural nails, and thus are easily peeled off and detached off by rubbing or contact with a liquid such as water, after being applied.
To solve such problems in using lacquers, there has recently been used a technique of curing manicure on nails using materials that are curable by chemical reaction.
For example, Patent Literature 1 discloses a curable composition for nail decoration comprising: a polyether urethane acrylate having a mass average molecular weight of 5500 or 8000; a compound having an alicyclic structure and an ethylenic unsaturated group; an acrylic monomer having a hydroxyl group; a photo-radical polymerization initiator; a radical polymerization inhibitor; and the like.
Patent Literature 2 discloses a photocurable manicure composition comprising: a urethane acrylate having a polyester backbone; a hydroxyl group-containing acrylic monomer; a carboxylic acid-modified polyester acrylate; a polyol compound; a photo-radical polymerization initiator; and the like.
Patent Literature 3 discloses an artificial nail composition comprising: an acrylic functional compound having a polyol backbone; an acrylic functional compound having a urethane backbone; photo-radical polymerization initiator; and the like.
Patent Literature 4 discloses a composition for manicure comprising: a urethane acrylate; a trifunctional acrylic monomer; a photo-radical polymerization initiator; and the like.
Patent Literature 5 discloses a color polish for nail manicure, comprising: a polyester urethane acrylate; a bifunctional acrylic monomer having a glycol backbone; an epoxy acrylate; and the like.